The subject of the invention is a device for the preparation of a fleece from inorganic and organic fibrous materials, such as mineral wool and glass wool, wherein the fibers of the web are irregularly erected relative to its plane of extension, and which serves as starting material for the production of fibrous products having resistance to pressure and high stability of shape, such as fibrous blankets, mats and plates.
Devices for the preparation of a fleece of inorganic or organic fibrous materials wherein the fibers are irregularly erect in relation to its plane of extension were previously unknown.
It is generally known that the fibers or fiber aggregates (henceforth called fibers) are led by an airstream produced by a blower, after their creation into a chamber where the fibers are deposited upon conveyor means and become a fleece. Fibers carried along by the airstream are sucked into the nascent fleece. That forces the fibers to adopt a position corresponding to the plane of the fleece.
It is a disadvantage of this process that the fleece does not become sufficiently voluminous, so that large amounts of material are needed for the creation of a fleece. Furthermore, the orientation of the fibers within the fleece does not allow for the production of fibrous materials with great resistance to pressure and with great stability of shape. That is countered by an expensive subsequent treatment of the fleece. Subsequent treatment is done, for instance, by stabilizing and hardening a web with binders, cutting it in parallel strips, turning the strips by 90.degree. and glueing the strips close together upon a supporting material (Information 105-Anwendungstechnische Mitteilungen der Deutschen Rockwool-GmbH, Gladbeck BRD).
For that, a large amount of material and technical appliances is needed as well as high costs of manufacture and upkeep, all facts which increase the costs of fiber products. Furthermore, a device for the manufacture of plush-like goods was disclosed. (DE-OS No. 2809019). It consists of a fiber distributor underneath of which was arranged in series: a grounded electrode formed as a classifying grid, a high voltage electrode developed as a charge grid, and close to the base another grounded electrode. The fibers, fed in by the conveyor, reach the electrostatic field through the classification grid, are aligned therein, and are brought upon the base after traversing the charge grid and the second grounded electrode. This device is not suited for the preparation of a fleece with irregularly erected fibers. The reason is that the very irregular fibers which are often balled together into larger aggregates plug up the passage apertures of the classification and charge grids instead of passing through, a fact which is apt to constantly interrupt the feeding of the fleece with fibers. Constant disturbances of production are the consequence, and the output of such devices is greatly diminished.
The object of the invention is to develop a device for the preparation of a fleece which makes it possible to minimize the amount of material for a fleece, to assure a continuous course of production and to considerably avoid subsequent treatment of the fleece for an increase of resistance to pressure and high stability against deformation.